Comparison of Surgical Outcomes between Trabeculectomy with Mitomycin C and Ahmed Valve Implantation with Mitomycin C in Eyes with Uveitic Glaucoma

Abstract

We compared 1-year outcomes of trabeculectomy with mitomycin C (MMC) and Ahmed valve implantation with MMC as a first surgical procedure in patients with uveitic glaucoma. A total 38 eyes of 38 patients undergoing trabeculectomy (n =16) or Ahmed valve implantation (n = 22) were included. Surgical success was defined as intraocular pressure (IOP) ≤21 mmHg, IOP reduction ≥20% from baseline, no secondary glaucoma surgery, and no loss of light perception. The main outcome measurements including success rate, IOP, and the number of antiglaucoma medications and complications were compared. The overall success rates were comparable between the Ahmed and trabeculectomy groups (81.3 vs. 81.8%, p = 0.987). The mean IOPs were similar as well (p = 0.084), though the number of antiglaucoma medications was significantly lower in the trabeculectomy group than in the Ahmed group (1.0 ± 1.2 vs. 2.2 ± 1.1; p = 0.005). A statistically significant reduction in corneal endothelial cell density was noted in the Ahmed group (p = 0.004). Both treatments offered reasonable IOP control and safety for eyes with uveitic glaucoma. However, significantly fewer antiglaucoma medications were used in the trabeculectomy group. Furthermore, our results suggest that cautious postoperative monitoring with regard to corneal endothelial cell density should be additionally performed after Ahmed valve implantation.

Uveitis and glaucoma: a look at present day surgical options

“…Lee et al quotes a surgical success rate of 88% at 6 months and 81% at 12 months for uveitic glaucoma patients who underwent Ahmed tube insertion. Surgical success was defined as IOP of less than 21 mmHg [23]. Chow et al quoted similar results with success rates of 86% at 6 months and 77% at 12 months in uveitic glaucoma patients who underwent Ahmed tube insertion [25].…”

“…At the 10-year follow-up, it was noted that 67% of patients still had an IOP of less than 18 mmHg, and 48% of patients had an IOP of less than 15mmHg [21 ▪ ]. Lee et al quoted similar results of 86% of uveitic glaucoma patients achieving IOP less than 21 mmHg, with or without medication posttrabeculectomy with MMC at 6 months and 82% at the 1 year mark [23].…”

“…Cazana et al [28 & ] noted that 25% of the patients who had the Baerveldt implant inserted experienced hypotony with 50% of these patients requiring revision surgery. Lee et al described that 13% of patients who had Ahmed tube implants inserted developed hypotony [23]. Sinha et al did a retrospective comparative study which showed that the Baerveldt implant was found to have a greater complication rate when compared with the Ahmed tube.…”

“…Lee et al . described that 13% of patients who had Ahmed tube implants inserted developed hypotony [23]. Sinha et al .…”

“…Both types of drainage devices are successful in controlling IOP in uveitic glaucoma patients [23,25,26]. Lee et al quotes a surgical success rate of 88% at 6 months and 81% at 12 months for uveitic glaucoma patients who underwent Ahmed tube insertion.…”